Mineral oil composition



. to reduce the corrosion problem.

Patented Feb. 19, 1946 2,395,093 MINERAL on. COMPOSITION John Bishop, .Wenonah, N. J., asslgnor to f Socony-Vacuum Oil Company, Incorporated, a corporation of New York No Drawing. Application April s, 1943, Serial No. 482,031

9 Claims. (CI. 25.2-51.5)

This invention has to do with lubricants and, more specifically, has to do with improvingg mirreral lubricating oils by incorporating therein a small amount of a mineral oil characterizing ingredient.

As is well known to those familiar with the art. mineral lubricating oils are characterized by certain undesirable features or shortcomings under various conditions of use. For example, in presout day engine operation, the lss stable constituents of such oils tend to oxidize and form acidic and gummy, or sludge-like, materials which corrode and scufl or wear metal engine parts. In this way, the efliciency of the lubricating action of the oil is substantially reduced and the useful life of the oil is correspondingly reduced. Mineral lubricating oils also possess the undesirable property of forming emulsions when in contact with water. This latter property is particularly detrimental in an environment such as is in a steam turbine inasmuch as emulsions interfere with the separation of the lubricant from water, both in the lubricating system and in the centrifugal washing operation. Oils of such caliber do not come up to the standards approved by the United States Government in certain tests which are described hereinafter.

Various additive materials have been proposed for use in mineral lubricating oils to counteract the aforesaid shortcomings of such oils. Numerous antioxidants or oxidation inhibitors have been used for such purposes, but while they have been found to reduce the formation of sludge-like materials in the oil and retard the emulsion-forming tendencies of the oil, they have not appreciably reduced corrosion of said metal parts. Also certain esters of fatty acids, as well as many fatty acids typical of which is stearl'c acid, have been incorporated in small amounts in lubricating oils In general, however, although oils containing fatty acids or alcohol esters do substantially prevent rusting of metal parts such as those used in turbines, they have the undesirable feature of producing emulsions when in contact with water.

It is one object of the present invention to impart anti-rusting and demulsifying" properties to mineral lubricating oils by the incorporation other obiect of the present invention to impart demulsifying properties to mineral lubricating oils containing an oxidation or corrosion inhibitor. Still another object is to impart demulsifying properties to said oils containing both an oxidation and a corrosion inhibitor. It is a further object of thisinvention to fortify said oils in these respects such that they conform to the standards established by the U. S. Government test methods and other test methods of the art. Still other objects will be apparent to those familiar with the art from the illustrative examples and test results provided hereinafter.

The present invention is predicated upon the discovery that the aforesaid objects are accomplished by the use of a small amount of an oilsoluble alcohol extract of blown lard oil in a mineral lubricating oil such as one used in turbine operation.

The oil-soluble alcohol extract of blown lard oil contemplated herein is prepared by contacting a blown lard oil with an alcohol,. removing the alcohol from the alcoholextract containing that portion of the blown lard oil which is soluble in the alcohol, and thereby obtaining said oil-soluble alcohol extract.

A preferred procedure for obtaining the min eral oil characterizing ingredient of the present invention is the following: Lard oil was heated and blown with air in a jacketed steam kettle until the Saybolt viscosity, at 210 F., of the oil was 158 seconds. The blown lard oil was heated in an open kettle with stirring at F. to F. with 2 to 2 times its volume of 95% ethyl a1- cohol until the mixture thus formed was thoroughly agitated. Then, heating and agitation were discontinued and the mixture was allowed to settle. Two layers were thus obtained; the upper being the alcohol solution of blown lard oil extract and the lower layer being the extracted blown lard oil, that is, the portion insoluble in the alcohol. The two layers were separated and the alcohol solution of blown lard oil extract (upper layer) was placed in a still suitable for reoilzalcohol ratios of from 1:1 to 1:25. The yields not extract ranged from 9.5% t 20.0% and the neutralization numbers (N. M.; mgms. KOH/ gram of extract) varied from 53 to 62. In each case, the extracts were substantially of the same degree of efiectiveness in fortifying mineral lubricating oils. In Table 1 given hereinafter, sample 1 represents that blown lardoil extract obtained from 50 grams of blown lard oil and an oilzalcohol ratio of 112. Sample 2 describes that extract obtained from 1 kilogram of blown lard oil and an oilzalcohol ratio of 1:2, and sample -3 is that extract obtained from 28 pounds of blown lard oil and an oil:a.lcohol ratio of 1:2.5. Sample 4 is a trial extraction with oilzalcohol ratio of 1:1. The yield obtained was 9.5%.

That the oil-soluble blown lardoil extract contemplated herein is extremely effective in improving the corrosion and emulsion characteristics of mineral oil fractions'is demonstrated by the results obtained by subjecting several blank oils and I oil blends containing said extract to the following corrosion (or rust) and emulsion, test methods.

One test method ,is designated as the proposed A. S. T. M. Rust Test Method and involves suspending a Polished steel specimen in 300 cc. of the oil under test at 140 F. for 30 minutes, then adding 30 cc. of distilled water and stirring the mixture at 750 R. P. M. for 48 hours. The steel specimen is removed from the water and oil mixture and examined for evidence of corrosion. The oil passes this test when there is no evidence of rust.

Another test method used herein was the Static Rust Test which involves placing a slightly concave, polished steel specimen in a beaker of oil under test at 90 F. for hour. A drop of dispass this test, specifications for mineral lubricating oils of viscosities shown on the'chart usually call for a continuous layer to be absent at the interface after 30 minutes.

Emulsion test 2 is the Emulsifying Oonstituents With Steam Test described in the Bureau of Ships pamphlet N. B. S. 431, Lubricating Oil, General Information, Requirements and Methods of Test. The emulsifying constituents with steam factor is determined by steaming 100 cc. or the oil and 20 cc. of distilled water in a 250 cc. cylinder for 10 minutes, after which the temperature of the cylinder and contents is maintained at 130 F. for 1 hour. If at the end of 1 hour there is no emulsion, the test is reported as none, and if there is an appreciable amount of emulsion present, the

test is reported as present.

Emulsion test 3 is the Steam Emulsion Test for lubricating oils described in the Federal Standard Stock Oatalog, Section IV, art 5, Federal Specifications VV-L-791b, Feb. 19, 1942, F. S. No. 320.61 or the A. S. T. M. Method D-l57-36. The Steam Emulsion Number (S. E. No.) obtained in this test is the number of seconds required Table 1 Emulsion test 1 Emulsion test 2 Time of separation Emul. test Proposed static rust (mins') with Emulsilying Time test constituents of sep., secs Dist 1% 1 N with steam mms.

water .salt N aOH on A 43 Not pessing Not passing. 011 B 5 11 20 None 21 83 do Do. 0110 a. s 16 s 110 do Do.

tilled water is then placed below the surface or the oil and on thesurface of the steel specimen. After 24 hours, the steel specimen is withdrawn from the beaker and is examined for rust. To

pass this test, the oil should not allow any rust 1942. In this test, 40 cc. of oil and 40 cc. of emulsant (water) in a 100 cc,.cylinder are.stirred with a paddle. at 1500 R. P. M. for' 5;minutes at the prescribed temperature. The separationof the.

emulsion is observed while the cylinder is kept at the prescribed temperature for the specified time. The figures given on the chart, provided in the reterence identified above, arethe actual times at which there is no continuous layer of emulsion remaining between the oil and wat Other fi ures shown are the cc. of emulsion remaining after the specified time interval.

The data set forth in Table 2 below represent results of the aforesaid tests in which oil blends of blank oils and various oilgaddition agents were used. Oil blends are show of said. blank oils and of a. typical oxidation inhibitor, a condensation (product obtained by reacting ethylaniline and formaldehyde as described in Patent 2,223,411, issued December 3, 1940; other oil blends are shown of the blank oils, the aforesaid typical oxidation inhibitor, and typical corrosion inhibitors, dioleyl malate and degras fatty acids.

Also shown are oil blends of said blank oils containing both the oil-soluble'alcohol extract of blown lard oil, the aforesaid typical oxidation inhibitor, and a typical corrosion inhibitor.

In Table 2, oil A is a so-called Light oil, identified by a Saybolt Universal viscosity at F. of 148-155 seconds; oil B is designated a. Heavy medium oil and is identified by thecharacteristics Saybolt Universal viscosity at 150 F. of 315-325 seconds; and oil C is a Heavy oil identified by Saybolt Universal viscosity at 130 F. of -205 seconds. Oils A, B and C are similar In order to 'to those shown in Table 1 above.

aseaoes 3 Table 2 Emulsion test 1. time of separation (mins.) with- E 2 Emma testa Proposed 1 Statcrust manned 185%! cent 1N Emitlistiiyiig 25 2: e31. No., nit t es t so ucons uen s secs. water 'tion NaoH with steam 33 1510.29,, ethyl-aniline-iormalde 76 Not passing. Not priming.

0.04% alc. extract blown lard oil 75 Pass ott iii i a a oey m a .i 133 do P 0.05 0 dloleyi meme-+0.04% alo. 45 ..-do Do. extractbiownlardoil(sample3). ollllyggii Lm ethyi-aniline-iormalde- 8 8 l3 None 3 92 Not passing- Not passing.

0.044810. extract blown lard oil -1a l5 30 do s 75 Pass (sample 2). 0.2% dioleylmalate 60o 1cc 60 1cc Present 60038cc 300 do Pass.

emu]. emul. emul 0.1% dioleyi malate+0.04% ale. 6 l5 26 None 5 71 do Do.

extract blown lard oil (sample 3). oi l g cm ethyl-aniline-formaldel7 l3 l5 do 3 160 Not passing- Not passing.

0.037; alc. extract blown lard oil 13 16 do 7.. 105 Pass..

(sample 1). r 0.05% alc. ext. blown lard oil .15-. 8 45. do 4 75 .do

(sample 1). 0.05% degree fatty acids 60 6001 cc 60-0-4 cc Present 60 35cc 300+ do Pass.

\ em emul em 0.2%dioleylmalate 53 50 36 do 9002 cc 215 ..do Do.

cm 0.05% degree fatty aeids+0.05% 21 17 35 None 110 do Do. alc. extract blown lard oil (sample 3). 0.1% dioieyl ma1ate+0.05% alc. 23 15 37 do 7 75 .d0 Do.

extract blown lard oil (sample 3). 0.2% dioleyl malate+ 0.075% ale. 27 33 do 4 70 do Do.

ext. blown lard oil (sample 3).

The results shown under the heading oil A indicate the relative effectiveness of various oil blends of oil A in the aforesaid emulsion and rust tests. An oil blend of oil A and a. typical antioxidant, ethylaniline-formaldehyde reaction product, reveals that the blend possesses good emulsion properties as shown by the S. E. number, but poor anti-rusting properties. on the other hand, an oil blend of oil A, the ethylanilineformaldehyde reaction product and a representative corrosion inhibitor, dioleyl malate, possesses good anti-rusting properties but poor emulsion properties. The oil blends or compositions contemplated herein and represented by the oil blends shown thereafter in Table 2 are superior to those already discussed in that they possess both the demulsifying and anti-rusting agent of this invention, oil-soluble alcohol extract of blown lard oil, an oxidation inhibitor and a corrosion inhibitor possess both excellent anti-rusting and emulsion characteristics.

Similarly, a comparison of the results shown in Tables '1 and 2 will clearly indicate that the alcoboth good emulsion characteristics and antirusting characteristics. It will be observed that the addition of only 0.04 of the oil-soluble alcohol extract of blown lard oil greatly improves the emulsion characteristics of the oil blend containing dioleyl malate and the ethylanilineformaldehyde reaction product.

The more extensive data. given for oil blends.

oi oil B point in the same direction asdo those ior oll A discussed above. For example, while the emulsion characteristics of the oil blend containing the typical antioxidant. ethylanilineformaldehyde condensation product, are good, its anti-rusting properties are undesirable. Also, the oil blend of oil B, the ethylaniline-formaldehyde reaction product and dioleyl malate has good anti-rusting properties but poor emulsion charhol extract of blown lard oil. contemplated herein, is a rust inhibitor and also imparts good emulsion characteristics to an oil. It will again be observed that typical corrosion inhibitors and typical oxidation inhibitors are not so characterized for they do not improve, and in general impair, the emulsion properties of the oil to which-they have been added.

It is to be understood'that the aforesaid oil blends are illustrative only and that the invention is not limited thereto. For example, viscous mineral oil fractions are contemplated herein; the preferred fractions, however, are

mineral lubricating oils typified by oils A, B, and

C, above, which are suitable for use in turbines. Also the oil-soluble alcohol extract of blown lard oil may be used alone in a minor proportion or amounts of from about 0.03% to about 0.1%, .and in oils containing either an oxidation inhibitor or a corrosion inhibitor, or both, in amounts of, from about 0.02% to about 0.30%.

It is also to be understood that the procedure given hereinabove for the preparation of the oilsoluble alcohol extract of blown lard oil of this invention is merely illustrative of one means by which the extract may be obtained. while this procedure is preferred, desirable extracts are obtained by varying the several factors invi'alved in the preparation. That is, ethyl alcohol 01 diflerent concentrations, other than 95%, may be used,

as may also other alcohols. 'The ratio of alcohol to blown lard oil, temperatures, inert gas used in the preparation, etc., may be modified. Similarly, the blown lard oil shown hereinabove is rep= resentative only of the type of blown lard oil which may be used. For example, the blown lard oil may be blown with air to a greater or lesser degree than the one shown, may be of different viscosity, and the N. N. thereof may vary over a wide range.

extract of blown lard 011. For example, this invention contemplates the use of the alcohol extract of blown lardoil in combination with materials such as alkyl aniline-formaldehyde condensation products, aromatic amines, phenolic derivatives, suliurderivatives, etc., and with rust inhibitors such as fatty acids, alcohol esters of fatty acids, estersofpoly basic acids, etc., or with combinations of anti-oxidants and rust inhibitors of the type conventionally used in lubricant compositions which are typified in the fore- The alcohol extract of blown going example. lard oil may also be used in combination with oils containing other additives instead of, or in ad dition to, the anti-oxidants and rust inhibitors above referred to. Detergents, such as oil soluble metal soaps, pour point depressants, viscosity index improvers, etc., are typicaladditives used in lubricating oils which may be improved in their emulsioncharacteristics by the blown lard oil extracts contemplated herein; Our experience indicates that the extract contemplated herein may be used in, combination with these other additives without detracting from the fu ile-f tion of the other additives and that the other ads.

ditives do not interfere with the effectiveness of the blown lard oil extract in improving the emul-' sion characteristics of the oil blend.

I claim:

1. An improved mineral oil composition comprising a viscous mineral oil fraction having in admixture therewith a minor proportion, sufli- [cient to retard the rustand emulsion-forming characteristics of said oil fraction, of an oil-sloluble alcohol extract of blown lard oil and a minor proportion sufficient to retard the deleterious effects of xidation upon said oil fraction, ofthe condensation product of ethylaniline and formaldehyde.

2. An improved mineral oil composition comprising a viscous mineral oil fraction having in admixture therewith a minor proportion, sum cient to retard the rustand emulsion-forming characteristics'of said oil fraction, of an oil-soluble alcohol extract of blown lard oil and .a minor prdportiomsuficient to retard the corrosivity at= tending said oil fraction, of dioleyl malate.

. ,3. An improved mineral oil composition comprising a viscous mineral oil fraction having in admixture therewith a minor, proportion, sumcient to retard the rustand emulsion-forming characteristics of said oil traction, of an oil-soluble alcohol extract of blown lard oil; a minor pro- 5 portion, sufllcient to retard the corrosivity at tending said oil fraction, of dioleyl malate; and

ble alcohol extract of blown lard oil obtained by blowing a lard oil with air, contacting the blown lard oil from the preceding operation, with alcohol, separating the alcohol extract layer and the extracted blown lard oil layer thus obtained, and removing the alcohol from the alcohol extract layer to obtain said oil-soluble alcohol extract of blown lard oil. 1

'5. An improved mineral oil composition com= prising a viscous mineral oil fraction having in admixture therewith a minor proportion of an oil-soluble alcohol extract obtained by blowing a lard oil with air until said lard oil was characterizedby a Saybolt Universal viscosity of about 158 seconds at 210 F., heating and agitating said blown lard oil with alcohol, separating the alcohol extract layer and the extracted blown lard oil layer obtained in thepreceding operation and distilling off the alcohol from the alcohol extract,

. lard oil with air until said lard oil was characterized by a Saybolt Universal viscosity of 158 seconds at 210 F., heating and agitating said blown lard oil with 95% ethyl alcohol, separating the ethyl alcohol extract layer and the extracted blown lard oil layer obtained in the preceding operation, and distilling off the ethyl alcohol from the ethyl alcohol extract layer to obtain said oilsoluble alcohol extract of blown lard oil.

7. An oil composition adapted for the lubrica- -;;.tion of ferrous metal surfaces in an environment containing water, comprising a viscous mineral oil fraction having in admixture therewith a minor proportion of an oil-soluble alcohol extract of blown lard oil, which is present in an amount sufficient to retard the rustand emulsion-forming characteristics of said oil fraction.

8. A turbine oil composition comprising a viscous mineral oil ,fraction having in admixture therewith a minor proportion, suificient to retard the rustand emulsion-forming characteristics of said oil fraction, of an oil-soluble alcohol extract of blown lard oil.

9. A turbine oil composition comprising a viscous mineral oil fraction having in admixture therewith from about 0.03 per cent to about 0.1 per cent of an oil-soluble alcohol extract of blown lard oil. i

, JOHN H. BISHOP.

characteristics or said 011 fraction, of an oil-solu- 

